bzoj 3224 splay模板题4

再刷水题我就废了。。。

 #include<iostream>
 #include<cstdio>
 #include<algorithm>
 #include<cstring>
 #define lc(x) ch[x][0]
 #define rc(x) ch[x][1]
 #define inf 0x3f3f3f3f
 #define N 200005
 using namespace std;
 int ch[N][];
 int k[N];int cnt,root;
 int size[N],fa[N];
 void push_up(int x)
 {
     size[x]=size[ch[x][]]+size[ch[x][]]+;
 }
 void rotate(int p)
 {
     int q=fa[p],y=fa[q],x=(p==ch[q][]);
     ch[q][x]=ch[p][x^];fa[ch[q][x]]=q;
     ch[p][x^]=q;fa[q]=p;
     fa[p]=y;
     if(y)
     {
         if(q==ch[y][])ch[y][]=p;
         else ch[y][]=p;
     }
     push_up(q);push_up(p);
     return ;
 }
 void splay(int x)
 {
     for(int y;y=fa[x];rotate(x))
     {
         if(fa[y])
         {
             if((ch[y][]==x&&ch[fa[y]][]==y)||(ch[y][]==x&&ch[fa[y]][]==y))rotate(y);
             else rotate(x);
         }
     }
     root=x;
 }
 int pre(int v)
 {
     int x=root;int tmp=-inf;
     while(ch[x][k[x]<v])
     {
         if(k[x]<v)tmp=k[x];
         x=ch[x][k[x]<v];
     }if(k[x]<v)tmp=k[x];
     return tmp;
 }
 int suc(int v)
 {
     int x=root;int tmp=inf;
     while(ch[x][k[x]<=v])
     {
         if(k[x]>v)tmp=k[x];
         x=ch[x][k[x]<=v];
     }if(k[x]>v)tmp=k[x];
     return tmp;
 }
 int find(int z)
 {
     int x=root;
     if(k[x]==z)return x;
     while(ch[x][k[x]<z])
     {
         x=ch[x][k[x]<z];
         if(k[x]==z)return x;
     }
     return ;
 }
 void insert(int z)
 {
     int x=root;size[x]++;
     while(ch[x][k[x]<z])x=ch[x][k[x]<z],size[x]++;
     cnt++;ch[x][k[x]<z]=cnt;k[cnt]=z;size[cnt]=;fa[cnt]=x;splay(cnt);
 }
 void del(int x)
 {
     splay(x);
     if(!ch[x][])
     {
         root=ch[x][];fa[ch[x][]]=;
     }
     else if(!ch[x][])
     {
         root=ch[x][];fa[ch[x][]]=;
     }
     else
     {
         fa[ch[x][]]=;int tmp=ch[x][];
         while(ch[tmp][])tmp=ch[tmp][];
         splay(tmp);ch[tmp][]=ch[x][];fa[ch[x][]]=tmp;
         push_up(tmp);
     }
     return ;
 }
 int fd(int kk,int x)
 {
     int l=ch[kk][];int r=ch[kk][];
     if(size[l]+==x)return k[kk];
     if(size[l]>=x)return fd(l,x);
     return fd(r,x-size[l]-);
 }
 int pr(int z)
 {
     int ans=;
     int x=root;
     while(x)
     {
         if(k[x]<=z)
         {
             ans+=size[ch[x][]]+;
             x=ch[x][];
         }
         else x=ch[x][];
     }
     return ans;
 }
 void yu()
 {
     root=;k[]=inf;cnt=;size[]=;
     insert(-inf);
 }
 int main()
 {
    yu();
    int n;
    scanf("%d",&n);
    for(int o=;o<=n;o++)
    {
          int t1,t2;
          scanf("%d%d",&t1,&t2);
          if(t1==)
          {
              insert(t2);
       }
       else if(t1==)
       {
           int x1=find(t2);
           if(x1!=)del(x1);
       }
       else if(t1==)
       {
           printf("%d\n",pr(t2-));
       }
       else if(t1==)
       {
            printf("%d\n",fd(root,t2+));
       }
       else if(t1==)
       {
            printf("%d\n",pre(t2));
       }
       else
       {
           printf("%d\n",suc(t2));
       }
    }
    return ;
 }